Case Study: Adding a CTA for Out of Stock Items

By Luke Hardwick

October 25, 2018


Using SiteSpect, this organization was able to add a CTA for out of stock items while integrating with their inventory software.

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This UK based health food retailer has a huge ecommerce component, and is always A/B testing ways to improve their user experience or streamline the shopping process. This brand had previously A/B tested factors like urgency messaging and zoom functionality on product detail pages. However, despite the overall conversion rates on product detail pages (which were good and improving), analytics showed that very few customers click on “Email Me” when they see out of stock items. Instead, most shoppers who make it to the product detail pages of an out of stock item don’t engage with the item further.

Adding Out of Stock Messaging to PLP

To streamline the customer experience, the brand decided to A/B test the positioning of its “out of stock” messaging. While the site displayed basic messaging about out of stock items on product list pages and search result pages it was not as clear as it could have been and presented no positive call to action. Customers often wouldn’t even discover a product was out of stock until they clicked and landed on product detail page.

The A/B test variation replaced the “Out of Stock” button on out of stock items on product list pages with an “Email Me When In Stock” call to action — a functionality that was already available on product detail pages. This allowed customers to quickly add themselves to a waiting list, and waste less time on out of stock items.

Implementing the Variations

This brand keeps track of their inventory with a third party software that allows the product detail pages to update and stay accurate. Because of SiteSpect’s architecture, we were able to integrate with the inventory software. So, during the A/B test, the inventory notices remained accurate while presented within the SiteSpect A/B test variations.

This A/B test also needed to be applied to many different pages. The “Email Me” button needed to appear on any product list page and any search result. With any other A/B testing software, this would require a complicated series of inserting JavaScript tags that would also slow down site performance and interfere with the inventory software. With SiteSpect, we were able to perform a global variation using our Search and Replace function. By searching for a particular code snippet and replacing it directly, we could make this change really simply in one task. SiteSpect also allows for server side and client side variations in one A/B test — that really made this A/B test possible.

Results and Next Steps

Moving the “Email Me When In Stock” button to the product list pages and search result pages increased user engagement by almost 150%. Interestingly product page views of out of stock items also increased by over 2% when visitors understood they could request an email. Considering the increase in customers notified when items come back into stock, the brand projected an annual revenue bump of £200,000. The variation was served to 100% of visitors immediately.

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Luke Hardwick

Luke Hardwick

Luke Hardwick is a Manager of Customer Success at SiteSpect, consulting for SiteSpect users on their optimization and personalization road maps and projects. Luke is based in London and has experience as an conversion rate optimization specialist across many softwares before landing at SiteSpect.

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